An auxiliary power unit (APU) may be provided with an inlet door that is moveable between a closed position and one or more open positions to allow airflow into the APU and accordingly provide the desired APU functionalities.
In some existing systems, a failure in the APU inlet door system could go undetected prior to allowing operation of the APU. This could lead to APU damage or loss of performance. There is therefore a need for an improved system and method for APU inlet door system testing.